Egg Counts Research Articles

A case-control genome-wide association study of estimated breeding values for resistance to gastrointestinal nematodes in two local dairy sheep breeds.

In sheep, gastrointestinal nematodes (GINs) can cause disease, reduced feed intake, and nutritional deficiencies. To counteract GINs, anthelmintics are widely used although it is well known they may enter the environment impacting ecosystems. In addition, anthelmintics resistance has rapidly developed and consequently, alternative approaches are crucial for profitable and sustainable sheep production. The occurrence of resistant individuals is mainly due to their intrinsic genetic diversity; therefore, the implementation of breeding plans for resistant animals may provide a promising strategy to reduce the use of anthelmintics. This study is aimed at identifying genomic regions involved in sheep resistance to GINs. To do this, faecal samples were collected from 642 Comisana and 323 Massese sheep over 3years to assess Faecal Egg Counts, and Estimated Breeding Values (EBVs) for GIN resistance were estimated by a repeatability animal model. Then, EBVs in the 99.95th and 0.05th percentiles were used to identify the most and least "genetically resistant" individuals to GINs, using genotyped individuals with the Illumina OvineSNP50 beadchip. A genome-wide case-control analysis was performed retaining the most significant single nucleotide polymorphisms (SNPs) with a threshold of 0.005% for the false discovery rate. Genes and Quantitative Trait Loci overlapping significant SNPs were annotated and enriched respectively while genes have been also enriched for functional pathways. As a result, 13 genes on 12 chromosomes and 10 genes on 11 different chromosomes were identified in the Comisana and Massese breed, respectively. Among these, genes involved in the physiology or pathology of the gastrointestinal tract, in adaptive processes and in production traits, were detected. The enrichment analysis highlighted 36 significant pathways in the Comisana breed and 21 in the Massese breed. Many of these pathways were involved in the regulation of the immune response, drug metabolism and detoxification, and vitamin metabolism. Interestingly, pathways involved in vitamin and drug metabolism were also identified in previous research and have shown to play an active role in GIN resistance. In this study, we took advantage of the use of EBVs as a metric for GIN resistance in a case-control genome-wide framework and successfully identified several genomic regions that might be involved in the trait. The presence of overlapping functional pathways related to different genes in the two breeds seems to reinforce the idea of the polygenicity of this trait, and further studies are needed in order to make selection schemes an effective tool to contrast GINs.

Knowledge, attitudes and practices of Australian dairy goat farmers towards the control of gastrointestinal parasites

BackgroundGastrointestinal parasites such as nematodes and coccidia are responsible for significant economic losses in the goat industry globally. An indiscriminate use of antiparasitic drugs, primarily registered for use in sheep and cattle, in goats has resulted in drug-resistant gastrointestinal parasites. Very little is known about the gastrointestinal parasite control practices used by Australian dairy goat farmers that are pivotal for achieving sustainable control of economically important parasites. The study reported here provides insights into gastrointestinal parasite control practices of Australian dairy goat farmers based on responses to an online survey.MethodsThe questionnaire comprised 58 questions on farm demography, husbandry and grazing management, knowledge of gastrointestinal parasites and their importance in dairy goats, diagnosis of infections, antiparasitic drugs and alternate control options. After a pilot survey (n = 15 respondents), a link to the questionnaire was available to all (n = 456) registered members of the Dairy Goat Society of Australia Ltd from 17 April to 16 June 2023. Multiple correspondence analyses (MCA) were performed to explore the association between selected parasite control practices.ResultsA total of 66 (14%) respondents completed the questionnaire. Of these, 74% (49/66) observed parasite-related illnesses in their goats; two-thirds of them assessed worms burden using faecal egg counts (FECs), with 26% (39/149) deworming their goats based on the results of the FECs. Most respondents (97%; 183/188) perceived that gastrointestinal parasites caused production losses and ranked Haemonchus contortus as the most important parasite. Anitparasitic drugs were used by 94% (62/66) of respondents, with the most frequently used anthelmintics being a commercial combination of four anthelmintics (levamisole, closantel, albendazole and abamectin), benzimidazoles and macrocyclic lactones. Most respondents (77%; 51/66) were unaware of anthelmintic resistance on their property. MCA results delineated two clusters of gastrointestinal parasites management.ConclusionsThis study provides insights into the demography of Australian dairy goat farms, the husbandry and grazing practices used by dairy goat farmers, their knowledge regarding gastrointestinal parasites and their practices for internal parasite control, thereby paving the way for tackling drug resistance in gastrointestinal parasites in dairy goats.Graphical

A STAND-ALONE TOOL FOR MOSQUITO EGG ENUMERATION.

Accurate enumeration of mosquito eggs is crucial for various entomologic studies, including investigations into mosquito fecundity, life history traits, and vector control strategies. Traditional manual counting methods are labor intensive and prone to human error, highlighting the need for automated systems. This study presents a stand-alone automated mosquito egg counting system using a Raspberry Pi computer, high-quality camera, light-emitting diode ring light source, and a Python script leveraging the Open Source Computer Vision library. Linear regression analysis comparing automated and manual counts yielded a slope of 1.009 and an R2 value of 0.999, indicating a strong correlation between the methods. Bland-Altman analysis showed a bias of -0.5, with 95% limits of agreement ranging from -11.88 to 10.88. These results demonstrate the high accuracy and reliability of this system in laboratory settings. The automated system's portability, cost-effectiveness, and independence from an external computer make it particularly useful for diverse research environments. Variability in egg size and potential inaccuracies in field conditions with multiple mosquito species highlight areas for further refinement, and future work will focus on optimizing the counting algorithm and validating its performance across different mosquito species and rearing conditions to enhance its applicability in vector research.

Reasons to be fearful? Rising proportions of positive faecal worm egg counts among UK horses (2007-2023).

Anthelmintic resistance (AR) threatens effective equine parasite control. Quarterly data summaries from faecal worm egg count testing (FWECT) performed by UK laboratories have appeared in Equine Quarterly Disease Surveillance Reports (EQDSR) since 2007, but have not previously been assessed. To assess strongyle FWECT methods and thresholds used by UK laboratories. To investigate factors associated with quarterly laboratory FWECT positivity rates between 2007 and 2023. Laboratory surveys and analysis of laboratory summary data. Laboratories were surveyed in Q3 2018 and again in Q4 2023. Proportions of FWECTs reported positive (PTP) each quarter by individual laboratories between 2007 and 2023 were analysed using multiple mixed-effects linear regression, evaluating laboratory-level random-effects and fixed-effects variables for ordered categories of FWECT-thresholds, year-quarters and consecutive year groups. Ten laboratories responded in 2018 and 13 laboratories in 2023. Samples were commonly reported positive at >0 to <100 eggs per gram (epg) and ≥200 epg. Regression modelling of 1190 EQDSR submissions confirmed significantly decreased PTP for thresholds ≥100 to <300 epg (level-2: -12.0%, p = 0.03), ≥300 epg (level-3: -18.0%, p = 0.03) and when thresholds were not specified (level-4: -12.2%, p = 0.0), relative to level-1 baseline (>0 to <100 epg). No significant seasonal variation in PTP between year-quarters was evident. Overall, controlling for between-laboratory variation and FWECT thresholds, there remained evidence for a significant gradient in increasing PTP over the study period relative to baseline (2007-2009). There were increases in PTP of +6.9% in 2010-2011 (p < 0.001), +10.1% in 2012-2013 (p < 0.001), +14.1% in 2014-2015 (p < 0.001), +16.0% in 2016-2017 (p < 0.001), +15.6% in 2018-2019 (p < 0.001), +17.1% in 2020-2021 (p < 0.001) and +18.9% in 2022-2023 (p < 0.001). Survey responses were limited and most laboratories' FWECT thresholds were not known. Controlling for laboratories and FWECT thresholds there was strong residual evidence from FWECT summary data for increasing egg counts in UK horses between 2007 and 2023.

Antibodies and Inflammation: Fecal Biomarkers of Gut Health in Domestic Ruminants.

Gastrointestinal infections present major challenges to ruminant livestock systems, and gut health is a key constraint on fitness, welfare, and productivity. Fecal biomarkers present opportunities to monitor animal health without using invasive methods, and with greater resolution compared to observational metrics. Here we developed enzyme-linked immunosorbent assays for three potential fecal biomarkers of gut health in domestic ruminants: two immunological (total immunoglobulin [Ig]A and total IgG) and one inflammatory (lactoferrin). We analytically validated the assays, then evaluated whether they could be used as a biomarker of clinically diagnosed gastrointestinal pathologies in cattle (Bos taurus), and finally comparedthem with helminth fecal egg counts in sheep (Ovis aries). The analytes were detected above the lower limits of detection in cattle, sheep, and goats. Fecal IgA and lactoferrin were higher in cattle with infectious pathologies (strongyles, coccidiosis and symptomatic Johne's disease) compared to healthy controls. Lactoferrin was additionally higher in animals with infectious pathologies compared to noninfectious pathologies, and to asymptomatic Johne's cases. No significant relationships were found with sheep fecal egg counts. These initial findings suggest that fecal IgA and lactoferrin may be useful biomarkers of poor gastrointestinal health in cattle, and that fecal lactoferrin is specific to active inflammation caused by infectious agents. These could be incorporated into the growing suite of noninvasive ecoimmunological tools and used to understand ruminant gut health in a range of species. Applications include improving treatment regimens for gastrointestinal infections, and understanding wildlife physiological responses to infectious challenges.

Using an Aqueous Suspension of Duddingtonia flagrans Chlamydospores and a Hexane Extract of Artemisia cina as Sustainable Methods to Reduce the Fecal Egg Count and Larvae of Haemonchus contortus in the Feces of Periparturient Ewes

Using an Aqueous Suspension of Duddingtonia flagrans Chlamydospores and a Hexane Extract of Artemisia cina as Sustainable Methods to Reduce the Fecal Egg Count and Larvae of Haemonchus contortus in the Feces of Periparturient Ewes

Discovery of Human PIM Kinase Inhibitors as a Class of Anthelmintic Drugs to Treat Intestinal Nematode Infections.

Soil-transmitted helminth (STH) infections affect one-fourth of the global population and pose a significant threat to human and animal health, with limited treatment options and emerging drug resistance. Trichuris trichiura (whipworm) stands out as a neglected disease, necessitating new drugs to address this unmet medical need. We discovered that several different chemical series of related human Provirus Integration sites for Moloney murine leukemia virus (PIM) family kinase inhibitors possess potent anthelmintic activity by using whole-worm motility assays. Systematic structure-activity relationship (SAR) studies based on the pan-PIM kinase inhibitor CX-6258 were conducted to identify compounds displaying improved in vitro motility inhibition of both adult hookworm (Ancylostoma ceylanicum) and adult whipworm (Trichuris muris) nematodes. A broad kinase selectivity screen of >450 human kinases confirms PIM1 kinase and others as potential targets for CX-6258 and analogues thereof. In addition, we demonstrated that CX-6258 significantly reduced worm burden and egg counts in the T. muris infection model of mice, establishing it as a new oral small molecule anthelmintic therapeutic.

Effects of lifetime feeding of hydrolyzed yeast to broiler breeders on egg production, quality, and hatchling attributes.

The effects of lifetime feeding of hydrolyzed yeast (HY) to broiler breeders (BB) on egg production, egg quality, and hatchling attributes were investigated. The birds were selected from two groups reared on diets with or without 0.05 % HY from hatch. The birds were placed for the current study at 22 weeks of age (woa) in 16-floor pens (20 ♀ and 2 ♂/pen) based on rearing diet identity. Isocaloric and isonitrogenous diets were formulated without or with 0.05 % HY for three production phases: 1 (22 to 40 woa), 2 (41 to 50 woa), and 3 (51 to 64 woa) and allocated within rearing diet identity in a completely randomized block design (n = 8). The birds had free access to water, whereas feed allocation was per breeder guidelines. Egg count/ pen was recorded four times daily from 25 woa (the time point the first egg was laid) to calculate hen day egg production (HDEP), and cumulative eggs per hen housed (CEPHH). From 28 woa, eggs were selected randomly for eggshell breaking strength (ESBS) and eggshell thickness (EST) and for incubation to determine fertility, hatchability, in-ovo mortality, chick sex ratio, and chick weight. Two hens per pen were necropsied at 44 and 64 woa for breast, abdominal fat and liver weights. There were no (P>0.05) interactions between diet and BB age or the diet effects on response criteria. Broiler breeder age effect (P<0.05) was such that HDEP, ESBS, EST, hatchability declined whereas egg weight, in-ovo mortality, and chick to egg weight ratio increased with age. Control birds had more (P=0.015) CEPHH (25 to 64 woa) than HY40 birds. In conclusion, the more CEPHH for the control group was reflective of hen mortality whereases the broiler breeder age effects were as expected. Overall, lifetime feeding HY to broiler breeders from hatch had no impact on egg production rate, egg quality and hatchling attributes.

Comparative assessment of Mini-FLOTAC, McMaster and semi-quantitative flotation for helminth egg examination in camel faeces

BackgroundFaecal egg counts (FECs) are essential for diagnosing helminth infections and guiding treatment decisions. For camels, no evaluations of coproscopic methods regarding precision, sensitivity and correlation between individual and pooled faecal samples are currently available.MethodsHere, 410 camel faecal samples were collected in 2022 from South Darfur State, Sudan, and analysed to compare the semi-quantitative flotation, McMaster and Mini-FLOTAC methods in terms of precision, sensitivity, inter-rater reliability and helminth egg count correlations, as well as the effects of pooling samples. Six samples were used to assess precision for McMaster and Mini-FLOTAC, while the remaining 404 samples were evaluated for sensitivity, inter-rater reliability and egg count correlations. Of these, 80 samples were used in pooling experiments.ResultsSix analyses of each sample (n = 6) using the McMaster and Mini-FLOTAC methods revealed no significant difference in the coefficient of variation between the two. For strongyle eggs, 48.8%, 52.7% and 68.6% were positive for McMaster, semi-quantitative flotation and Mini-FLOTAC, respectively. The sensitivity of the three methods showed only minimal improvement when three egg counts were performed on the same sample. McMaster and Mini-FLOTAC had similar sensitivity for Strongyloides spp. (3.5% frequency), while it was lower for semi-quantitative flotation at 2.5%. Mini-FLOTAC was more sensitive for Moniezia spp., detecting 7.7% of positives compared with 4.5% for semi-quantitative flotation and 2.2% for McMaster. For Trichuris spp., frequencies were 0.3% with Mini-FLOTAC, 0.7% with McMaster and 1.7% with semi-quantitative flotation. Mini-FLOTAC also detected higher strongyle eggs per gram (EPG) of faeces (mean 537.4) compared with McMaster (330.1). More samples exceeded treatment thresholds with Mini-FLOTAC, with 28.5% of animals having EPG ≥ 200 compared with 19.3% for McMaster, while 19.1% showed EPG ≥ 500 with Mini-FLOTAC compared with 12.1% with McMaster. There was no significant correlation between individual and pooled strongyle FECs, as indicated by Pearson correlation coefficients of r ≥ 0.368 (P ≥ 0.113) and Spearman correlation.ConclusionsMini-FLOTAC outperformed semi-quantitative flotation and McMaster in diagnosing helminth infections in camels, offering greater sensitivity and detecting higher EPGs, particularly for strongyles, Strongyloides spp. and Moniezia spp. Thus, treatment decisions based on Mini-FLOTAC EPGs will lead to more treatments.Graphical

First report of ivermectin resistance in natural infected Foals by Parascaris spp. in Tiaret, Algeria

Equine parascarosis is a Worldwide endoparasitosis, caused by Parascaris spp., affecting mainly younger horses. This disease is considered as the most pathogenic parasitosis of young horses. In Algeria, no knowledge of the resistance of Parascaris spp. to Ivermectin is published. For this reason, the present study aims to evaluate the frequency of Parascaris spp. and the anthelmintic efficacy of Ivermectin and Fenbendazole against this parasite in a foal population in Tiaret, Algeria. Ninety–one foals were examined for the presence of Parascaris spp. from two stud farms. Among the positive, thirty–two faols were treated with Ivermectin formulations (Ivoral® and Eqvalan®) and Fenbendazole (Funcur®) at their recommended dosages. Fecal egg count reduction testing (FECRT) was used to determine the efficacy of each anthelmintic. Parascaris spp. was detected in 61 foals (67.03%). Decreased efficacy (reduction of Parascaris spp. fecal egg counts by less than 90%) was found for the two Ivermectin formulations (46.45% for Ivoral® and 70.29% for Eqvalan®). Nevertheless, fenbendazole showed 100% efficacy in all foals sampled in this study. These first data indicate that Ivermectin–resistant Parascaris spp. populations are present on horse farms in Algeria. Findings from this study can be used to create a more sustainable approach for parasite control programs.

Egg reappearance periods associated with anthelmintic treatments given to horses in winter and summer over two years.

Shortened egg reappearance periods (ERP) have been seen as an early warning of anthelmintic resistance development in cyathostomins in horses. The hypothesis has been that in these instances, efficacy against egg laying adult cyathostomins remains high, but a decline in activity against later larval stages leads to the earlier resumption of egg shedding after treatment. In this study using a single herd of horses we investigated the ERP of a number of commonly used equine anthelmintics and examined whether ERP might show seasonal variation between winter and summer. Four main Faecal egg count reduction tests (FECRT1-4) were conducted respectively in Winter (Jun/Jul) 2019, Summer (Jan/Feb) 2020, Winter 2020 and Summer 2021. The tests examined the efficacy and ERP of ivermectin, moxidectin, abamectin and fenbendazole. Egg counts of two groups of horses were monitored before and for 6-7weeks after treatment - however long it took for counts to return to at least 10% of what they had been before treatment. One additional FECRT was also conducted, using a second abamectin-containing product (FECRT5 - Spring 2020). Treatment with ivermectin (FECRT1-4), moxidectin (FECRT 1-2) and the first abamectin product tested (FECRT3) all reduced egg counts by >99% for 4weeks after treatment, with ERP of 5-7weeks and with minimal differences between the 3 treatments. There was a tendency for counts to rise more rapidly in summer, and in the second year of testing as opposed to the first. Both the second abamectin product (FECRT5) and the fenbendazole (FECRT4) were found to be ineffective, reducing egg counts immediately after treatment by 68 and 52% respectively.

Absolute eosinophil count and expression analyses of cytokine genes in Haemonchus contortus resistant Malpura sheep: Role of TH1/TH2 cytokine dichotomy.

A strong Th2-type immune response against Haemonchus contortus infection in genetically resistant sheep provide immunity. The objective of present study was to correlate mean faecal egg counts (FECs), absolute eosinophil counts and Th1/Th2 gene expression in resistant (R) and susceptible (S) Malpura sheep. In spite of no anthelmintic treatment in R line, on majority of the months, mean FECs remained significantly (P<0.05) lower compared to S line where anthelmintic treatment was given in September every year. R sheep possess a smaller number of blood eosinophils in the majority of months as compared with S sheep and a positive correlation has been observed between absolute eosinophil counts and mean FEC. In the condition, when FEC remain similar in both the lines (R and S), significantly (P<0.05) up-regulated expression of IL-5 was observed in R sheep compared with S sheep however when FEC is hugely enhanced; IL-2, IL-6, IL-12 and IL-13 gene expression was significantly (P<0.05) up-regulated in R sheep as compared to S sheep which is dependent on season and parasite load.

Assessing the benzimidazole resistance in equine strongyles by in vitro methods.

The study aimed to conduct a survey on the occurrence of benzimidazole (BZ) resistance in strongyles by in vitro egg hatch test (EHT) and larval development test (LDT) and to identify the effective indicators of early resistance detection on horse farms with associated risk factors analysis appraisal. In total, 203 horses from 8 farms underwent the fecal sampling of which 77 horses were selected for in vitro testing. Simultaneously, 18 horses were chosen to analyse the results of in vitro tests compared to the in vivo fecal egg count reduction test (FECRT). The EHT indicated the presence of resistant strongyles in all farms with an exceeded threshold of 0.1 μg/ml thiabendazole (TBZ) in 43 horses (55.84 %). The percent egg hatch at 0.1 μg/ml TBZ in "resistant parasites" varies from 39.0 ± 6.0 % to 91.0 ± 1.0 %. The hatching range between 8.5 ± 1.5 % and 50.0 ± 6.0 % at a concentration of 0.1 μg/ml TBZ was detected wherein the recommended threshold was not exceeded. The analysis of the EHT results demonstrated that egg hatching at the 0.1 µg/ml TBZ concentration was identified as the most important predictor of the early detection of BZ resistance. In the LDT, the mean TBZ concentration which interrupted the development of 50 % and 99 % larvae to the infective stage (L3) from all horses was 0.0753 ± 0.0454 and 0.6798 ± 1.9144 μg/ml TBZ, respectively. Only cyathostomin L3 were found at TBZ concentrations ≥ 0.08 μg/ml and only in samples from 81.8 % of horses (36/44). A comparison of LDT results did not show a statistically significant agreement with EHT and FECRT. In conclusion, the in vitro EHT could be implemented as an indicator for early BZ resistance detection and showed that monitoring of hatching at selected concentrations could detect presence and estimate the proportion of the resistant parasite population on the horse farms.

A deep learning-based method for silkworm egg counting

A deep learning-based method for silkworm egg counting

Ovipositional preferences of fall armyworm, Spodoptera frugiperda, on different host plants under laboratory conditions

The interaction between insects and their host plants is essential for understanding successful oviposition, particularly for polyphagous insects. The fall armyworm (FAW), Spodoptera frugiperda, is a significant pest affecting over 300 host plant species. In light of its impact, an experiment was conducted to examine FAW oviposition on Brassica rapa L., B. oleracea var. capitata, and Zea mays L. Results from this study revealed a notable influence of host plant species on FAW oviposition preferences. The highest egg count (675 ± 32.4 eggs) was recorded on maize, specifically on the maize strain of FAW. In choice experiments, the FAW maize strain showed a strong preference for ovipositing on maize. Interestingly, neither the mustard strain (139 ± 37.3 eggs) nor the cabbage strain (37.0 ± 4.6 eggs) laid the highest number of eggs on their respective host plants. Among reproductive parameters, the primary difference observed was in the oviposition period. For adult diets, the highest fecundity, with 1188 ± 64.84 eggs, was achieved with a honey + protein solution diet. These findings suggest that adult diet has a substantial impact on oviposition period and can be beneficial for mass-rearing FAW in laboratory settings. In conclusion, the results indicate that FAW in Pakistan still shows a strong preference for maize and has not adapted to other host plants as primary options. This preference for maize warrants focused pest management strategies to keep FAW populations below threshold levels and minimize crop damage.

The influence of crop and leaf position on thrips (Thysanoptera: Thripidae) oviposition in cotton, soybean, and peanut seedlings.

Thrips (Thysanoptera: Thripidae) can injure seedling cotton (Gossypium hirsutum L.), soybean (Glycine max (L.) Merr.), and peanut (Arachis hypogaea L.) crops in the southern United States. The planting window and timing of thrips infestations into these crops overlap in the region, but thrips preference for oviposition has not been investigated. We evaluated thrips preference for cotton, soybean, and peanut by counting eggs, immatures, and adults at the cotyledon to 4 true leaf stages. Peanut was significantly more attractive for oviposition than cotton and soybean. Oviposition in cotton was significantly higher in the cotyledons than the other leaves. The highest oviposition in soybeans also occurred in the cotyledons but differed only significantly from the fourth true leaf. In all crops, there was no significant difference among oviposition in the true leaves. The highest number of immatures were found on cotton, followed by peanut and then soybean, while adults were evenly distributed among crops. Our results suggest that while peanut is preferred for oviposition, this crop may not facilitate immature development and survival as effectively when compared with cotton. This study presents an initial examination of crop selection by thrips under field conditions and suggests peanut may be the preferred oviposition host.

Optimum sugar syrup feeding intervals for Apis cerana Fab. during the winter dearth period in the sub-tropical area of Nepal

The study aimed to identify the optimal sugar syrup feeding interval for honeybee colonies during the winter dearth period in subtropical region of Nepal to ensure colony survival and maintenance. The focus was on evaluating sealed brood area, sealed honey area, egg-laying activity, and pollen collection. The experiment was conducted in an apiary located in Lamjung district of Nepal. Sugar syrup (1 water: 1 sugar) was fed to honeybee colonies at intervals of 7, 10, 15, and 20-days, along with a control group. Each treatment was replicated across four replications with five beehives in each replication, and data were collected weekly. Parameters such as the sealed brood area, honey storage, egg-laying rate, and pollen cells were measured by counting eggs, pollen cells, and assessing areas covered by sealed brood and honey. Colonies fed sugar syrup at 15-days intervals exhibited the best performance across all measured parameters, including the largest sealed brood area, highest honey reserves, maximum eggs laid by the queen bee, and the most pollen cells. These results indicate that feeding at 15-days intervals supports optimal colony health and activity during low-temperature winter conditions. Feeding sugar syrup at 15-days intervals is the most effective practice for maintaining colony health, ensuring optimal honey reserves, brood production, and pollen collection during the winter dearth period in subtropical areas of Nepal. This feeding strategy is recommended for improving colony survival, maintenance, and overall performance during challenging winter conditions in subtropical region of Nepal.

A novel sustained-release agent based on disulfide-induced recombinant collagen hydrogels for the prevention and treatment of Schistosoma infections.

Schistosomiasis is commonly managed using the praziquantel, but it is only effective against adult worms and duration of action is short. Liver fibrosis will worsen if eggs are still present after stopping treatment. Therefore, this study aimed to develop a sustained drug release system for effectively preventing and treating schistosomiasis. A disulfide bond-induced three-dimensional (3D) recombinant collagen hydrogel was developed for sustained praziquantel release. Three collagen sequences were developed based on the sequence for Scl2 of S. pyogene, with different substitutions of residues for cysteine (S-VCL-S1, S-VCL-S2, and S-VCL-S3). Their properties were tested. Mice were infected with Schistosoma japonicum cercariae and treated either with praziquantel collagen hydrogel or niclosamide collagen hydrogel. The worm-killing effect was examined. The application of hydrogel-niclosamide on the skin for 24 h effectively prevented Schistosome cercariae from infecting mice and showed 70.95% and 81.73% reduction in the number of eggs and worms, respectively. The combined use of niclosamide and anti-cercariae cream showed 100% protection after 24 h. The hydrogel-praziquantel also showed a 100% reduction of worms and eggs after 24 h of subcutaneous injection. The subcutaneous injection of praziquantel after 28 days of infection showed 95.19% and 80.12% reduction of worm and egg counts, respectively, and the development of larvae was significantly slowed down. Liver analysis showed no infection after 7 days of treatment. These results suggest developing a novel type of sustained-release agent against schistosomiasis based on the recombinant collagen hydrogel that provides a potential new treatment for schistosomiasis.IMPORTANCEThis study introduces an new way for treating schistosomiasis: a special collagen hydrogel that gradually releases medication to treat schistosomiasis effectively. This innovation provides a promising way to treat schistosomiasis. It represents a significant step forward in the fight against this disease and offers hope for more effective and safer treatments in the future.

Enhancing vector control: AI-based identification and counting of Aedes albopictus (Diptera: Culicidae) mosquito eggs

BackgroundDengue fever poses a significant global public health concern, necessitating the monitoring of Aedes mosquito population density. These mosquitoes serve as the disease vectors, making their surveillance crucial for dengue prevention. The objective of this study was to address the difficulty associated with identifying and counting mosquito eggs of wild strains during the monitoring of Aedes albopictus (Diptera: Culicidae) density via ovitraps in field surveys.MethodsWe constructed a dataset comprising 1729 images of Ae. albopictus mosquito eggs from wild strains and employed the Segment Anything Model to enhance the applicability of the detection model in complex environments. A two-stage Faster Region-based Convolutional Neural Network model was used to establish a detection model for Ae. albopictus mosquito eggs. The identification and counting process involved applying the tile overlapping method, while morphological filtering was employed to remove impurities. The model’s performance was evaluated in terms of precision, recall, and F1 score, and counting accuracy was assessed using R-squared and root mean square error (RMSE).ResultsThe experimental results revealed the model’s remarkable identification capabilities, achieving precision of 0.977, recall of 0.978, and an F1 score of 0.977. The R-squared value between the actual and identified egg counts was 0.997, with an RMSE of 1.742. The average detection time for a single tile was 0.48 s, which was more than 10 times as fast as the human–computer interaction method in counting an entire image.ConclusionsThe model demonstrated excellent performance in recognizing and counting Ae. albopictus mosquito eggs, indicating great application potential. This study offers novel technological support for enhancing vector control effectiveness and public health standards.Graphical

Mixed strongyle parasite infections vary across host age and space in a population of feral horses.

Identifying factors that drive among-individual variation in mixed parasitic infections is fundamental to understanding the ecology and evolution of host–parasite interactions. However, a lack of non-invasive diagnostic tools to quantify mixed infections has restricted their investigation for host populations in the wild. This study applied DNA metabarcoding on parasite larvae cultured from faecal samples to characterize mixed strongyle infections of 320 feral horses on Sable Island, Nova Scotia, Canada, in 2014 to test for the influence of host (age, sex and reproductive/social status) and environmental (location, local density and social group membership) factors on variation. Twenty-five strongyle species were identified, with individual infections ranging from 3 to 18 species with a mean richness (±1 s.d.) of 10.8 ± 3.1. Strongyle eggs shed in faeces were dominated by small strongyle (cyathostomins) species in young individuals, transitioning to large strongyles (Strongylus spp.) in adults. Egg counts were highest in young individuals and in the west or centre of the island for most species. Individuals in the same social group had similar parasite communities, supporting the hypothesis that shared environment may drive parasite assemblages. Other factors such as local horse density, sex, date and reproductive/social status had minimal impacts on infection patterns. This study demonstrates that mixed infections can be dynamic across host ontogeny and space and emphasizes the need to consider species-specific infection patterns when investigating mixed infections.